Evaluation of Cervico-vertebral Dimensions and Cranio-cervical Angulations in Adults with Different Vertical Growth Patterns: A Cross-sectional Cephalometric Study

Abstract

Introduction: The measurement of cervical vertebrae is a valuable diagnostic aid since it provides data on skeletal maturity and potential for growth. Research suggests the existence of a relationship between dentofacial characteristics and cranio-cervical morphology and posture. This relationship can provide insights into the development and treatment of malocclusions, particularly malocclusions in the vertical dimension. Aim: To compare cervico-vertebral dimensions, morphology, and cranio-cervical postures in subjects with different skeletal growth patterns such as average, horizontal and vertical. Materials and Methods: The study was cross-sectional in design and was conducted for a period of two years between January 2014 and December 2016 at KLE Society’s Institute of Dental Science and Research, Bengaluru, Karnataka, India. A total of 102 lateral cephalograms were taken for the study and classified into three groups according to Frankfurt Mandibular Plane Angle (FMA angle) and Jarabak ratio as Horizontal (HR), Vertical (VR), and Average (AV) groups. Each group comprised 34 subjects (17 males, 17 females). A total of 28 morphological parameters of C3, C4, and C5 in the lateral cephalogram were measured and analysed. Each lateral cephalogram was scanned with a Konica Minolta Bighub Laser printer, and the area measurement was made with IMAGE J software to measure the area of cervical vertebrae. One-way Analysis of Variance (ANOVA) was used to compare the various parameters between the three groups, and pair-wise comparisons were done using the Least Significant Difference (LSD) test. Student's t-test was done to assess the differences between males and females. A p-value less than 0.05 was considered statistically significant. Results: The mean chronological age of subjects was 21.2±3.14 years for the HR group, 21.3±3.78 years for the VR group, and 21±3.76 years for the AV group. There was a statistically significant difference between the three groups in the measurements of the anterior body height of C3 (ABHC3) (p=0.023), posterior Body Height of C3 (PBHC3) (p=0.007), vertical measurements of C3 (H3) (p=0.010) and (W3) (p=0.013), anterior body height of C4 (ABHC4) (p=0.010), Posterior Body Height of C4 (PBHC4) (p=0.005); H4 (p=0.002); Ratio of H4 and W4 (H4/W4) (p=0.048); area of the third cervical vertebrae (C3) (p=0.039) and area C4 (p=0.024). For cranio-cervical angulation, there were statistically significant differences found for the angle between the Nasion Sella Line (NSL) and the tangent to the Odontoid Process (NSL/OPT) (p<0.001), where the VR group had significantly larger values than the HR and AV groups. There was no significant difference found in fusion anomalies of cervical vertebrae among all three (HR, VR, and AV) groups. Conclusion: The study found that individuals with a horizontal growth pattern tend to have larger cervical vertebral dimensions compared to average and vertical growers. Individuals with a vertical growth pattern exhibited a large cranio-cervical angulation. Overall, males had larger cervical vertebral dimensions compared to females. The studied population did not exhibit any fusion anomalies.

Keywords

• cervical vertebrae
• malocclusion
• orthodontics
• posture
• vertical dimension